Saying he has not been honest with his family and constituents, Rep. Anthony Weiner today admitted that he exchanged graphic photos with six women over Twitter and Facebook, but said he will not resign, even as Democratic leaders called for an ethics investigation.

"I have not been honest with myself," a tearful Weiner said today, adding that it was a "hugely regrettable mistake."

The New York Democrat said some of the relationships dated back three years and that he generally met the women on Facebook. He added that he did not have a physical relationship with any of the women and that he mistakenly treated it as a "frivolous" thing.

"[I] have engaged in several inappropriate conversations ... with women I have met online," he said. "[I'm] deeply ashamed of my terrible judgment and actions. ... This was a very dumb thing to do."

Weiner said he did not use his work computer to carry on the Internet affairs and that his BlackBerry, from which he sent photographs, does not belong to the U.S. Congress. He also said several times he will not resign.

"Nothing about this should reflect in any way on my official duties or oath of office," he said. "I engaged in inappropriate online conversations. ... I don't believe I did anything that violates any law or rule."

Weiner, however, has his work cut out for him when it comes to convincing his fellow members of Congress. Minority leader Nancy Pelosi and Democratic Congressional Campaign Committee chair Steve Israel both called for an ethics committee investigation.

"I am deeply disappointed and saddened about this situation; for Anthony's wife, Huma, his family, his staff and his constituents," Pelosi, D-Calif., said in a statement. "I am calling for an Ethics Committee investigation to determine whether any official resources were used or any other violation of House rules occurred."

Weiner said he welcomes the investigation and will fully cooperate with the committee.

The 46-year-old congressman said today he never met the women and to the best of his knowledge they were all adults and were engaging in the conversations consensually.

"I've never had sex outside my marriage," he said.

Weiner called the news conference, but before he took the stage, the man who broke the story, conservative blogger Andrew Breitbart, got there first and took the mic himself.

Breitbart first said he was there to watch himself be vindicated, but then took to the podium and criticized Weiner for claiming that his Twitter and Facebook accounts had been hacked, and the media for its coverage of the story.

"This is a legitimate story," he said from the same podium from where Weiner was set to speak. There "is a continual attempt to blame the messenger."

Breitbart today got the apology he was demanding from Weiner, who also apologized to the media for lying.

Earlier today, Breitbart posted a shirtless photo of Weiner that the congressman allegedly sent to another woman. Though the picture only shows half the subject's face, the chin, chin and nose all resemble Weiner's.

Breitbart said he had an X-rated photo that he believed was of Weiner, but that he had no intention of releasing it, with the hopes of saving Weiner's marriage.

In the news conference today, Weiner admitted that he had sent an X-rated photo to one of the women.

Biggovernment.com also reported that a young woman said she received intimate photos and e-mails from the married congressman, including one of him with his cats titled "Me and the pussys."

That woman, Meagan Broussard, a 26-year-old single mother from Texas, revealed to ABC News today that she began the sexually charged electronic relationship with Weiner on April 20 and exchanged hundreds of explicit messages and photographs with him.

Weiner, who married Secretary of State Hillary Clinton's aide Huma Abedin last year, last week claimed his account was hacked when a photo of a man's crotch in just his underpants was sent from his Twitter account to a 21-year-old college student. But in multiple interviews, the once-rising star of the Democratic party did not directly deny that it was him in the photograph, fueling further media speculation.

Today, the 46-year-old congressman admitted the picture was his and that he sent it "as part of a joke." But when he realized it was posted to his Twitter account, he panicked.

"To be clear, the picture was of me and I sent it," he said.

Asked why he lied, Weiner said "I was embarrassed," and he "didn't want it to lead to other embarrassing things."

Weiner said Abedin knew of his Internet affairs when they got married last July but did not know until this morning whether he had been telling the truth about the Twitter posting.

"She was very unhappy. She was very disappointed," he said. "She also said she loved me ... but she deserves much better than this and I know that."